Process of manufacturing antislipping tires for motors and other vehicles.



.No Drawing.

" STATES PATENT OFFICE.

ANDRE monmm, or PARIS, FRANCE.

,PROCESS OF MANUFACTURING ANTISLIPPING- TIRES FOR PIOTOIR-S AND OTHER l VEHICLES.

To all whom it concern:

Be it known that I, ANDRE: MICHELIN, a

citizen of the Republic of France, and resident of Paris, in the 'Republic .of France,

have invented certain new and useful Improvements in Processes of .Manufacturing Antislippiiig Tires for Motors and other Vehicles, of which the following is a speci-' fication.

My invention relates to a process of making wheel tires, the object being to produce a tire in which leather and rubber are united without injuring in. any way the qualities of the leather. and, so as to provide a tire which will resist the heat arising during its use on the vehicle.

Hitherto leather has only entered into the manufacture of pneumatic tire casings by means of a cold vulcanization process. In the manufacture of ant-iskidding tire casings, the layers composed entirely or partially of leather are cemented by means of rubber solutions in a cold process, and, if

the leather is secured, either by sewing or by rivets, on to a rubber layer, the cementing of this layer of rubber on to the under layers ofrubber is also made by acold process in order to avoid heating and consequentlyinjuring the leather.-

Now, processes of cementing by rubber solutions In a cold process'are ob ect1onable because the tire thusmanufactured is not able to resist the heat generated by the friction on the road durin the time the vehicle is in motion, and,'besi es, the cementing cannot be complete around the buttons or interior I Washers of the metallic antiskidding device;

these antiskidding pieces having left about them some open spaces which can only be filled by pure, rubber.

It has heretofore been proposed to unite leather to rubber by a hot vulcanization, but

,ithas been thought necessary in carrying out this process to remove the grease and oil contained in the leather therefrom. Now, the result of this removal of the dily substances has been to deprive the leather of its flexibility and its quality of resisting atmospheric agents, with the result that this proess could not be adapted for the manufacture ofcasings for pneumatic tires having a protecting strip of leather. I have discovered by experimentation that the condition of being anhydrous is necessary and is of itself sufiicient to permit leather to Specification of Letters Patent. Pain-gutted Feb, 27, 1912, Application filed April 2, 1907. Serial No. $66,060 s undergo without deterioration the temperature necessary for a hot vulcanization; and that consequently it is only necessary to remove from the leather the water which it contains, while leaving in it all the greasy matters calledstufling in order to carry out thereafter a hot dry vulcanization process for uniting the .leatherto the rubber.

The following experiment is conclusive. If one takes a sample of ordinary leather of commerce andrenders it anhydrous by dry ing it in a hot air stove at a temperature below 1Q0 C. and then immediately on removing it from the stove it is plunged into anhydrous oil or grease at a temperature of aboutl40 0.; the leather withdrawn from this oily bath after an hour has not become deteriorated in any Way. On the contrary, if a sample of this same leather is exposed to the ,air for several hours afterdts re drawn from this bath, that it has been transformed partially into gelatin. Consequently the water is the single and only cause of deterioration inleather when it is submitted to a temperature of from 130 to 140 C.

Myinvention consists in a process of manufacturing an antiskidding tire casing including a layer composed of friction fabric covered with a band of leatheranda rubber cushion interposed; between the fabric and the leather; the whole being united by a hot vulcanization process, This entire layer, leather, fabric, and rubber, is traversed by metallic rivets, the heads of which rest upon the" outer surface of the leather and the washers of which are riv- ()n this last mentioned surface is placed a thick layer of rubber by means of a hot vu1-- eted on the rubber on the opposite surface.

canization process, which layer is adapted to completely cover the Washers of the rivets and also to bind the part of the tire containing the leather to the carcass during the hot vulcanizing process.

In order that the vulcanization may be carried out Without injuring the leather, it is necessary that the latter shall be previously rendered anhydrous, that is to say, placed in a stove-at a temperature below- 100 C. for the purpose .of evaporating from the leather'the hygrometric water which it contains. This removal of the watermay be carried out before or after the leather is riveted to the -friction fabric. 'The indispensable condition and the only necessary condition is that the leather shall be anhydrous .at the moment ofbeginning the hot vulcanization and that it shall be mainstained anhydrous throughout the vulcanization. In order to this last mentioned. condition, there may be employed several known means of vulcanization by dry heat, such, for instance, as heatin by direct contact with metallic molds w ich' are themselves heated by hollow plates provided with an internal circulation of-steam; heat ing by contact with .elec'tric resistances;

heating by conductibility with some material dlvided up intosmall parts, such as lead shot; heating by hot gas; or by hot anhydrous liquid.

The vulcamzation of the pneumatic tire casing may be carried out at 'one' step by one of the'processes above mentioned after the incorporation of the leather, or, indeed,

certain parts, as for'example the carcass proper, or the outer la er not provided with the leather,'may su mitted to a previous vulcanization, partial or complete, by means of'steam.

That I claim is:

- 1. The process of incorporating leather as an element in tires which consists in rendering the leather anhydrous while per mitting the oils and greases to remain 'therein, second, applying a layer of crude rubber or of hot vulcanizing solution thereto, third, associating the leather with the other elements of the tire, and finally, subjectinghthe whole to dry vulcanizingheat.

e pnfiess of incorporating leather as an elementin tires which consistsin,

rendering the leather anhydrous, applying a layer of. rubber between the leather and the tread of the tire, applying a layer of rubber between the tread and the body of the tire, and finally subjecting the tire to a I have signed my name 1n 

